1. Field of the Invention
The present invention relates to an image processing apparatus and method.
2. Description of the Related Art
Processing a plurality of input images to generate a single output image is a known art. Among the image processing devices that generate a single output image from a plurality of input images, the image processing device described in patent document 1, for example, uses a function that is monotonically decreasing with respect to a distance from a position (I′, J′) to derive weighting coefficients for interpolation such that when a pixel value is calculated for position (I′, J′), it will be more strongly influenced by pixels in closer positions.    Patent document 1: Japanese patent No. 4496883 (paragraphs 0144, 0148, 0149)    Patent document 2: Japanese patent No. 2897772
When a pixel value for position (I′, J′) is calculated by interpolation using weighting coefficients derived by using a function that is monotonically decreasing with respect to the distance from the position (I′, J′) such that the interpolated pixel value will be more strongly influenced by pixels in closer positions, inappropriate pixel values may be obtained for some images.
Particularly when there are portions such as edges at which the luminance changes greatly near position (I′, J′), the interpolation results become inappropriate, causing distracting changes in luminance value in the output image.